某三轴水泥搅拌桩深层短桩质量控制及治理措施  

Quality control and treatment measures of deep short pile of a three-axis cement mixing pile

作　　者：刘宏伟 郑建璐 刘爱民[3] LIU Hong-wei;ZHENG Jian-lu;LIU Ai-min(Tianjin Lingang Public Utility Group Co.,Ltd.,Tianjin 300450,China;Tianjin Bohai Marine Monitoring and Surveillanced Management Center,Tianjin 300450,China;CCCC Tianjin Port Engineering Institute Co.,Ltd.,Tianjin 300222,China)

机构地区：[1]天津临港公用事业集团有限公司,天津300450 [2]天津市渤海海洋监测监视管理中心,天津300450 [3]中交天津港湾工程研究院有限公司,天津300222

出　　处：《中国港湾建设》2019年第9期42-45,共4页China Harbour Engineering

基　　金：天津市自然科学基金(一般项目)(16JCQBJC21700)

摘　　要：针对深层三轴水泥搅拌桩短桩,在黏性土层施工中常遇到成桩困难、强度低、不均匀、桩底标高不足等问题,以控制成桩质量、减少水泥用量、优化施工工艺和解决施工过程存在的问题为目的,通过调整施工工艺、改变水泥掺量等措施,进行了大量的现场验证性试验。现场试验结果表明:短桩施工应充分考虑水泥流失量,适当提高水泥掺量,桩身无侧限抗压强度才能满足要求;试验桩的施工工艺最终确定为:四喷四搅,下沉速度1 m/min、提升速度0.5 m/min,桩底标高处静喷60 s,水灰比为1.0;为了保证桩底成桩质量,需超深进尺不少于0.5 m。研究成果可为同类工程提供参考和借鉴。Aiming at the deep three-axis cement mixing pile short pile, the problems such as pile-forming difficulty, low strength, uneven and insufficient elevation of pile bottom are often encountered in the construction of viscous soil layer, in order to control the quality of pile, reduce the amount of cement, optimize the construction technology and solve the problems existing in the construction process, by adjusting the construction technology and changing the cement content , a large number of field validation tests have been carried out. The field test results show that the cement loss amount should be fully considered in the construction of short pile, and the unconfined compressive strength of piles can meet engineering requirements by properly increasing the cement content;the construction process of this project was determined as follows: four-spray four-stirring, sinking speed 1 m/min, lifting speed 0.5 m/min, static spray 60 s at the height of pile bottom, water-cement ratio of 1.0;in order to meet the elevation of the pile bottom, the ultradepth footage must be not less than 0.5 m. The research results can provide references for similar projects.

关 键 词：三轴水泥土搅拌桩 短桩 水泥掺量 施工工艺 取芯检测 

分 类 号：U655.544[交通运输工程—港口、海岸及近海工程] TU43[交通运输工程—船舶与海洋工程]